Note 8 - Fair Value of Financial Instruments - Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financial Assets:
Securities	$ 243,585	$ 179,148
Other Equity Securities	10,339	8,627
Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Securities
Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Securities	235,551	170,486
Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Securities	8,034	8,662
Reported Value Measurement [Member]
Financial Assets:
Cash and Short-Term Investments	51,875	116,411
Securities	243,585	179,148
Mortgage Loans Held for Sale	280	201
Loans - Net	1,287,686	966,519
Cash Value of BOLI	24,442	23,200
Other Equity Securities	10,339	8,627
Total	1,618,207	1,294,106
Financial Liabilities:
Deposits	1,354,071	1,055,533
Borrowings	102,572	80,501
Total	1,456,643	1,136,034
Estimate of Fair Value Measurement [Member]
Financial Assets:
Cash and Short-Term Investments	51,875	116,411
Securities	243,585	179,148
Mortgage Loans Held for Sale	280	201
Loans - Net	1,271,359	952,113
Cash Value of BOLI	24,442	23,200
Other Equity Securities	10,339	8,627
Total	1,601,880	1,279,700
Financial Liabilities:
Deposits	1,344,936	1,046,096
Borrowings	106,876	81,059
Total	1,451,812	1,127,155
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Cash and Short-Term Investments	51,875	116,411
Securities
Mortgage Loans Held for Sale
Loans - Net
Cash Value of BOLI
Other Equity Securities
Total	51,875	116,411
Financial Liabilities:
Deposits
Borrowings
Total
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Cash and Short-Term Investments
Securities	235,551	170,486
Mortgage Loans Held for Sale	280	201
Loans - Net
Cash Value of BOLI	24,442	23,200
Other Equity Securities
Total	260,273	193,887
Financial Liabilities:
Deposits
Borrowings	106,876	81,059
Total	106,876	81,059
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Cash and Short-Term Investments
Securities	8,034	8,662
Mortgage Loans Held for Sale
Loans - Net	1,271,359	952,113
Cash Value of BOLI
Other Equity Securities	10,339	8,627
Total	1,289,732	969,402
Financial Liabilities:
Deposits	1,344,936	1,046,096
Borrowings
Total	$ 1,344,936	$ 1,046,096

Represents the fair value portion of other equity securities.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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No definition available.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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Fair value portion of mortgage loans held-for-sale.

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